#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<assert.h>
char* my_strcat(char* dest,const char* scr)
{
	assert(dest&&scr);
	char* p = scr;
	char* ret = dest;
	while (*(++dest)!='\0')
	{
		;
	}
	while (*(dest++)=*(p++))
	{
		;
	}
	return ret;
}
int main()
{
	char arr1[20] = "abcd";
	//char arr2[] = "eft";
	my_strcat(arr1, "eft");
	printf("%s", arr1);
	return 0;
}